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81.
Examination of agonist interactions of imidacloprid on recombinant chicken α4β2 and Drosophila SAD/Chicken β2 hybrid receptors, expressed in Xenopus oocytes by nuclear injection of the cDNAs, indicates that imidacloprid is a partial agonist. Replacement of the α4 subunit for the Drosophila SAD subunit lowered the imidacloprid EC50 37-fold, whereas EC50s for other agonists increased 4-50 fold, suggesting that the α subunit contributes to the high affinity of insect nicotonic receptors for imidacloprid. ©1999 Society of Chemical Industry  相似文献   
82.
RNA-seq data analysis of cigarette beetle (Lasioderma serricorne) strains having different sensitivities to pyrethroids identified sodium channel mutations in strains showing pyrethroid resistance: the T929I and F1534S mutations. These results suggest that reduced sensitivity of the sodium channel confers the pyrethroid resistance of L. serricorne. Results also showed that the F1534S mutation mostly occurred concurrently with the T929I mutation. The functional relation between both mutations for pyrethroid resistance is discussed.  相似文献   
83.
Tea cultivars have been bred by individual selection of landraces and by crossbreeding, but the validation of the parentage is limited. In this study, we performed parentage analysis of 79 tea cultivars in Japan based on SSR markers to confirm or identify the parent-offspring relationships among them. The effectiveness of nine SSR markers for parentage analysis was validated by comparing them to the existing cleaved amplified polymorphic sequence markers. The former markers were detectable more alleles than the latter. Simulation of parentage analysis of the tea cultivars predicted biparental origins for 12 cultivars (‘Houshun’, ‘Mie ryokuhou no. 1’, ‘Surugawase’, ‘Tenmyo’, ‘Yamanoibuki’, ‘Harumidori’, ‘Koushun’, ‘Minekaori’, ‘Okumusashi’, ‘Saemidori’, ‘Sofu’, and ‘Toyoka’), in the first five of which candidate parents of yet-to-be-defined pedigree were newly identified. Comparisons of a total of 41 SSR genotypes confirmed the newly-identified parentages of ‘Asahi’ for ‘Tenmyo’, ‘Rokurou’ for ‘Houshun’, ‘Surugawase’, and ‘Yamanoibuki’, and ‘Yamatomidori’ for ‘Mie ryokuhou no. 1’. The maternity of seven cultivars out of the 12 was also confirmed with chloroplast DNA sequences. Uniparental origins were confirmed for 25 cultivars. This parentage analysis has improved our knowledge of tea pedigrees and will aid in the development of new cultivars.  相似文献   
84.
In this study, we determined light perception capability in juveniles and sub-adults of L. vannamei by means of electroretinogram (ERG) measurements. Eyes were assumed to be dark-adapted when the response magnitude had stabilized after 70–80 min under dark conditions. ERG responses elicited by mono-wavelength (336–694 nm) stimuli of equal intensity were determined in individual dark-adapted specimens. Relative spectral response curves determined from the amplitudes of on and off relative responses were found to be significantly different in juveniles and sub-adults. Both maximum on relative spectral response magnitudes were observed at 544 nm, but the on relative spectral response magnitudes of sub-adults to 518 nm were higher than for juveniles, and the on relative spectral response magnitudes of sub-adults to 568 nm were lower than for juveniles. The on and off relative spectral response curves of juveniles were steeper than those of sub-adults, while the on relative spectral response magnitude of juveniles was lower than that of sub-adults from 336 to 544 nm. The off relative spectral response magnitude of juveniles was higher than that of sub-adults from 518 to 597 nm.  相似文献   
85.
Fractionation of nuclear extracts of mouse embryoid bodies (EBs; OTT6050) on sucrose gradients (5-20%) under conditions of physiological ionic strength (150 mM NaCl, 1mM MgCl2) and an analysis of the RNA in various fractions by gel electrophoresis revealed that the major U small nuclear ribonucleoproteins (U-snRNPs; U1a, U1b, U2, U4, U5 and U6-snRNPs) sediment over a wide region of the gradient, although they sediment preponderantly in the light region of the gradient. This result suggests that, under these experimental conditions, some of the populations of snRNPs exist as free particles separated from large nuclear RNP particles, while some of the populations associate with them in EBs. Furthermore, all species of these major U-snRNPs appear to associate with the larger nuclear RNP particles of EBs, since all these species sediment in the heavier fractions (approximate greater than or equal to 60S) of the 15-40%/50% gradients. The relative abundance of the various species of major U-snRNPs can also be observed to vary among the fractions of the gradients. A similar analysis of the post-mitochondrial cytoplasmic fraction showed that some leakage of the major U-snRNPs, but not the selective leakage of any particular species of U-snRNP, from the nuclear fraction, occurred during aqueous fractionation of the cells. Some species of RNA, larger than the snRNAs U1a/b and U2 respectively were also detected in the cytoplasmic fraction.  相似文献   
86.
Some immortalized lens epithelial cell lines have been established and are useful for molecular analysis. The establishment of additional cell lines must, however, enable a variety of in-vitro examinations. The objective of this study was to establish a new canine lens epithelial cell line by isolating CLC-1 cells from the lens tissue of a dog with cataracts. In CLC-1 cells, transforming growth factor beta (TGF-β) treatment significantly decreased gene expression of an epithelial marker and elevated that of mesenchymal markers; these characteristics are similar to those of a human lens epithelial cell line. Interestingly, CLC-1 cells exhibited lower expression of an epithelial marker and higher expression of mesenchymal markers than an anterior lens capsule. These results suggest that CLC-1 cells were derived from a cell population that was committed to epithelial-mesenchymal transition in cataract lens tissue. In conclusion, CLC-1 cells could be useful for analyzing molecular pathogenesis in canine cataracts.  相似文献   
87.
In the present study, 15 canine ovaries without morphological lesions were examined histologically and immunohistochemically by using a large number of proteins including AE1/AE3, cytokeratin7 (CK7), CK13, CK20, vimentin, desmin, alpha smooth muscle actin (alphaSMA), calponin, S100, Neurofilaments, Inhibinalpha, placental alkaline phosphatase (PLAP) and neuron-specific enolase. Ovarian structures observed in this study included surface epithelium (SE), cortical tubules (CT), tunica albuginea (TA), stromal cells (SC), internal endocrine cells (IE), rete ovarii (RO) and fallopian tubes (FT). SE, CT, RO and FT were broadly immunoreactive for desmin. Besides AE1/AE3 and vimentin, desmin was also closely linked to these structures. Rete ovarii forming a reticular structure showed a positive reaction to S100. Surface epithelium was immunoreactive for PLAP at a significantly high level. In conclusion, these results indicate a specific segment of immunoreactivity as well as the broad range of immunoreactivity in canine ovary. The distinct patterns of immunoreactive for various kinds of proteins will play an important role in facilitating their identification and discrimination even in a normal canine ovary with a complex structure.  相似文献   
88.
CD30 ligand (CD30L) and tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) are members of the TNF-superfamily that have many important biological activities in cell proliferation and apoptotic death. In this study, both genes in the chicken were cloned and their expression was analyzed. Complementary DNA fragments were obtained from a suppressive subtractive hybridization library with or without lipopolysaccharide (LPS)-stimulation. Chicken CD30L consists of 1,152 base pairs (bp) with an open reading frame (ORF) of 720 bp having 36.4% identity with human CD30L, whereas chicken TRAIL is 1,134 bp long with an ORF of 912 bp having 54.4% identity with human TRAIL. Chicken CD30L was expressed at high levels in the spleen, bursa of Fabricius and in the chicken monocytic leukemia cell line, IN24. Stimulation with LPS in the spleen, bursa of Fabricius and the IN24 cell line did not affect CD30L expression. The gene expression of chicken TRAIL was essentially to the same level in all tissues examined. The time course of expression was not significantly altered by LPS-stimulation in the spleen, thymus and bursa of Fabricius, but reached a maximal level 8 hr after stimulation in the IN24 cell line. The high level expression of both genes in lymphoid organs and IN24 cell line indicates that chicken CD30L and TRAIL may also play an important role in apoptotic signal transduction and the regulation of cell proliferation in the immune system.  相似文献   
89.
An unusual case diagnosed as connective tissue-type mast cell leukemia with marked mastocyte infiltration into visceral organs in a seven-year-old female Curly-Coated retriever is presented. Acute circulatory collapse, emesis, diarrhea, abdominal enlargement, icterus, cyanosis, dyspnea, pulmonary edema, hepatomegary, ascites, and right ventricular enlargement were observed. Hematologic and biochemical examinations revealed mast cell leukemia, mature neutrophilia, monocytosis, thrombocytopenia, hemolytic hyperbilirubinemia, hyperhistaminemia, renal and hepatic injuries. Mast cells were distributed systemically, but predominantly in the diaphragm and liver with a large mass among the serosa of ileum, cecum and colon. Mast cells were stained intensely by both safranin and berberine sulfate.  相似文献   
90.
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